The rate and progression of aging varies from person to person and are further influenced by environmental factors, lifestyle choices, and/or physical fitness. In some instances, studies have shown that the state of the epigenome (e.g., mutation within the genome and/or methylation) correlate with age. As such, DNA methylation are utilized, for example, for determining age or changes in the rate of aging based on environmental factors, lifestyle choices, and/or physical fitness.